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Search Results: 1 - 10 of 14323 matches for " NATALE WILLIAM "
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Absor??o e redistribui??o de nitrogênio (15N) em Citrus mitis Bl
Revista Brasileira de Fruticultura , 2002, DOI: 10.1590/S0100-29452002000100040
Abstract: the absorption of nitrogen fertiliser labelled with 15n was studied in citrus mitis bl. the sources of n fertiliser used were ammonium sulfate, urea, calcium nitrate and potassium nitrate. all of them were applied in soil. a completely randomised design was utilised. the distribution of n in the different parts of the plants was determined after 10 and 20 days. there were no difference among treatments on plant dry matter weight and n content. the highest recovery of labelled n after 10 days was obtained with urea (14%). in the second sampling (20 days), the highest recovery was accomplished with ammonium sulfate (31%).
Absor o e redistribui o de nitrogênio (15N) em Citrus mitis Bl
Revista Brasileira de Fruticultura , 2002,
Abstract: Com a avalia o da eficiência de uso do nitrogênio, tem-se melhor entendimento dos aspectos nutricionais e respostas à aduba o. O presente ensaio teve por objetivo estudar a absor o e redistribui o de nitrogênio (15N) em Citrus mitis Bl.. As fontes de fertilizante utilizadas foram: sulfato de am nio, uréia, nitrato de cálcio e nitrato de potássio. O delineamento experimental utilizado foi inteiramente casualizado, com 4 tratamentos e 3 repeti es. Foram realizadas duas amostragens, aos 10 e 20 dias após a aplica o do adubo marcado, a fim de determinar os teores de N nas diferentes partes da planta. Através dos resultados, verificou-se que n o houve efeito dos tratamentos sobre o peso de matéria seca e conteúdo de N nas plantas. A eficiência de absor o de N variou com a natureza do fertilizante nitrogenado e com a época de amostragem, ao passo que a redistribui o do N n o foi afetada. A eficiência máxima de absor o do N variou de 14% (uréia) e 31% (sulfato de am nio), respectivamente, aos 10 e 20 dias após a aplica o do 15N.
Uso da grade aradora superpesada, pesada e arado de discos na incorpora??o de calcário em profundidade e na produ??o de milho
Prado, Renato de M.;Natale, William;
Engenharia Agrícola , 2004, DOI: 10.1590/S0100-69162004000100019
Abstract: the objective of the present study was to assess the effect of the modes of lime incorporation on the correction of soil acidity and on corn production. an experiment was conducted on typic hapludox of clay texture in uberlandia - mg, brazil, from may 1995 to march 1997. the experimental design consisted of a split-plot scheme. the main plots consisted of the modes of lime incorporation: heavy harrow (14 disks of 0.86 m) and leveling harrow (60 disks of 0.56 m); disk plow (4 disks of 0.66 m) and a leveling harrow; super heavy harrow (14 disks of 0.86 m) and a leveling harrow. the subplots were doses of dolomitic lime of 0; 6 and 9.2 t ha-1. the mode of lime incorporation affected the efficiency of liming in terms of soil profile. the heavy harrow was inadequate for lime incorporation. plowing with a super heavy harrow plus level harrowing showed a satisfactory performance, reaching a depth of as much as 0.20 m. harrowing with a super heavy harrow provided a greater uniformity and depth of incorporation, with neutralization of soil acidity to a depth of 0.30 m. corn responded in a linear manner to lime incorporation, with the mode of incorporation by harrowing with a super heavy harrow providing a greater production.
Desenvolvimento inicial e estado nutricional do maracujazeiro em resposta à aplica??o de lodo têxtil
Prado, Renato de Mello;Natale, William;
Pesquisa Agropecuária Brasileira , 2005, DOI: 10.1590/S0100-204X2005000600015
Abstract: in the treatment of liquid effluents of the textile industry the textile sludge results as residue. this work aimed at evaluating the effect of sludge application to the substrate of production of passion fruit cuttings in the development, and nutritional status of plants. experimental design used was randomized blocks with five treatments and four replications. the textile sludge was applied in the doses of 10, 15, 20 and 30 g per pot (dry base), corresponding 10, 15, 20 and 30 t ha-1, respectively, and a control without application. plants were fertilized with n, p, k, zn and b at 300, 450, 150, 5, and 0.5 mg dm-3, respectively. the experimental unit was represented by pots with 2 dm3 of a red latosol (oxisol) (v = 29%). after 100 days the textile sludge corrected soil acidity. however, in doses superior to 10 t ha-1 it caused plants death. the textile sludge increased the content of n, k, s, b, mn and zn, reduced ca and mg content, and it didn't alter cu and fe content of passion cuttings dry matter.
Calagem na nutri??o de cálcio e no desenvolvimento do sistema radicular da goiabeira
Prado, Renato de Mello;Natale, William;
Pesquisa Agropecuária Brasileira , 2004, DOI: 10.1590/S0100-204X2004001000008
Abstract: the application of lime in acid soils improves the plant root system and, consequently, enhances water and nutrients absorption by the plants. the objective of this work was to evaluate the effects of lime application on the development of root system and calcium nutrition of guava plants cultivated in an acid distrofic red latosol (typic hapludox). soil samples were collected in four equidistant points, at 75 cm of the trunk and at 0-20 cm and 20-40 cm of depth, in the plots that had received zero (control), 3.7 and 7.4 t ha-1 of lime. soil samples were chemically analysed. lime material was applied at planting, incorporated with grating and moldboard plow. on the second and third years after guava plantation, effects of liming in chemical properties were determined. forty two months after lime incorporation in the soil (third year of guava plants cultivation), samples of roots were collected with a cylindrical auger, for dry mass and calcium content evaluation. samples of leaves were also collected. liming corrected soil acidity increased base saturation and improved calcium availability to plants and, consequently, improved guava root system. calcium concentrations of 30 mmolc dm-3 in the soil and of 7.5 g kg-1 in the roots were associated with the highest guava root growth.
Efeito da aplica??o de silicato de cálcio no crescimento, no estado nutricional e na produ??o de matéria seca de mudas de maracujazeiro
Prado, Renato de M.;Natale, William;
Revista Brasileira de Engenharia Agrícola e Ambiental , 2005, DOI: 10.1590/S1415-43662005000200006
Abstract: this work was carried out with the objective of evaluating the effect of the addition of industrial residue (calcium silicate) to the substrate in the production of the passion fruit seedlings, studying the benefits in the development, the production of dry matter and the nutritional state of the plants. the experimental design adapted was a randomized block with 5 treatments and 4 repetitions. the doses of calcium silicate applied were equivalent to raise in half; one; one and half; and twice the dose to elevate percentage of base saturation = 50%, corresponding to the 0; 0.45; 0.90; 1.35 and 1.80 g per pot, respectively, besides a control without application. the experimental unit was constituted of pots with 2 dm3 of a red latossol (oxisol). after 80 days of the plantation, the height, stem diameter, number of leaves and the dry matter of the shoot and the root, as well as contents of macro and micronutrients were evaluated. the passion fruit seedlings responded to the calcium silicatie application. the maximum development was associated with the base saturation of 58% with the concentrations of ca in the soil equivalent to19 mmolc dm-3 and the content of ca in the shoot of 12.0 g kg-1.
Efeitos da aplica??o da escória de siderurgia ferrocromo no solo, no estado nutricional e na produ??o de matéria seca de mudas de maracujazeiro
Prado, Renato de Mello;Natale, William;
Revista Brasileira de Fruticultura , 2004, DOI: 10.1590/S0100-29452004000100038
Abstract: the basic slag can consist in an alternative source of ca and mg, as well as punishment of soil acidity improving the nutricional state of passion plants, and determining the success of the implantation of an orchard. thus, it was objectified to evaluate the effect of siderurgy slag iron-chromium, in the alterations of the chemical attributes of the soil, in the nutrition of the plants and the development of passion seedlings. for this, it was installed an experiment in conditions of greenhouse, using the following increasing doses of the residue: zero; half; once; once and half and twice to raise v =80%. after 30 days of incubation of the slag in the soil, it was proceeded the plantation of the passion seedlings, in substratum of a distrofic, acid red latossol (pot with 2,8 dm3), cultivating them per 85 days. the application of the siderurgy slag iron-chromium promoted the neutralization of the acidity of the soil, however, in doses relatively low (360 kg ha-1) resulted in reduction in the nutrients and the production of dry matter of passion seedlings.
Foliar Nutrient Balance Standards for Maize (Zea mays L.) at High-Yield Level  [PDF]
Viviane Cristina Modesto, Serge-étienne Parent, William Natale, Léon Etienne Parent
American Journal of Plant Sciences (AJPS) , 2014, DOI: 10.4236/ajps.2014.54064

Maize is one of the most nutrient demanding staple crops. Tissue nutrient diagnosis of maize is currently conducted using critical nutrient concentration or dual ratio ranges, but such diagnoses are pathological as biased by data redundancy, sub-compositional incoherence and non-normal distribution. The use of orthogonal balances, a compositional data analysis technique, avoids such biases. Our objective was to develop foliar nutrient balance standards for maize. We collected 758 grain yields (15.5% moisture content) and foliar samples at silk stage in maize fields of southern Quebec, Canada, and analyzed ten nutrients in tissues (N, P, K, Ca, Mg, B, Cu, Zn, Mn, Fe). Nutrients were arranged into ad hoc balances and computed as isometric log ratios (ilr). An optimized binary classification performed by a customized receiver operating characteristic procedure showed that a critical Mahalanobis distance of 4.21 separated balanced from imbalanced specimens about yield cut-off of 11.83 Mg grain·ha-1 with test performance of 86%. Quebec maize balance standards differed from published standards computed from DRIS norms collected in other agroecosystems. The Redfield N/P ratio in maize leaves was found to be the least variable balance across regions of the world. The DRIS dual ratios and raw concentration values were found to be geometrically inadequate for conducting diagnosis. The unbiased nutrient balance diagnosis combined the critical Mahalanobis distance and a mobile representation of nutrient balances with ilr means of true negative (TN) specimens centered at fulcrums and back-transformed ilr values of TN specimens into raw concentrations loading the buckets below.

Influência da Aduba??o Fosfatada - Potássica na Ocorrência de Pragas na Cultura da Soja
Neotropical Entomology , 2002, DOI: 10.1590/S1519-566X2002000300014
Abstract: this study was developed to determine the effect of phosphate-potassic fertilization on the occurrence of soybean insect pests. plots were arranged in a randomized complete block design in a 4 by 4 factorial experiment (four phosphate levels and four potassic levels) with three replications. the levels of phosphorus and potassic tested were, respectively: 0, 80, 120 and 160 kg/ha of p2o5 and 0, 40, 60 and 80 kg/ha of k2o. the insect population survey was carried out on a weekly-basis starting from the v2 stage, using ground-cloth. the results showed a tendency of population growth of piezodorus guildinii (westwood) for the highest levels of nutrients. some leaf nutrients were correlated with diabrotica speciosa (germar).
Teor de fósforo e pH no bulbo molhado, com diferentes freqüências de fertirriga??o, utilizando ácido fosfórico
Foratto, Leticia C.;Zanini, José R.;Natale, William;
Engenharia Agrícola , 2007, DOI: 10.1590/S0100-69162007000300012
Abstract: phosphated fertilizers, such as superphosphate, triple superphosphate and monoamonium phosphate, applied throught drip irrigation can present pipe incrustations and emitters obstructions. in this research, carried out in the unesp - s?o paulo state university, jaboticabal - brazil, it was studied the phosphorous distribution, the influence on ph and the moisture in one oxisoil, fertigated during one month, with five applications of phosphoric acid. four replications and eight treatments were applied, and the treatments combined two rates of p2o5 (0 and 50 kg ha-1) and four frequencies of applications (1; 3; 5 and 7 days). the irrigation or fertigation frequency did not influence the distribution of the moisture in the wet bulb; ph of the soil until 30 cm from the drip and until 40 cm in depth was reduced, reaching value of 3.6 while the phosphorous values were higher in this same region of the bulb, exceeding 1,500 mg dm-3. these results allow indicating that the phosphoric acid can be used in localized irrigation systems, controlling soil ph, because low soil ph will be able to influence the development of the cultures and, consequently, the productivity.
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